A spring system and method for production of spring system

Abstract

A spring unit containing a spring system used in bed, armchair and sofa like constructions and realizing different hardness and comfort levels in different areas of the constructions and having a soft spring forming a soft comfort area of low hardness of the spring unit, a medium hard spring providing gradual transition between soft comfort areas of the spring unit and hard comfort areas with a spring a having number of convolution different from the soft spring and of the same wire diameter, and a hard spring providing hard comfort area of the spring unit by a spring having number of convolution different from the soft spring and medium hard spring and of the same wire diameter as the medium hard spring and soft spring.

1 . A spring unit used in bed, armchair and sofa like constructions and realizing adjustment of different hardness and comfort levels in different areas of said constructions characterized in comprising:
 at least a soft spring of one single wire diameter forming soft comfort area of low hardness area of said spring unit;   at least a medium hard spring providing gradual transition between soft comfort areas of said spring unit and hard comfort areas with a spring having number of convolution different from said soft spring and of same wire diameter;   a spring system comprising at least a hard spring providing hard comfort area of said spring unit by means of a spring having number of convolution different from spring of soft spring and medium hard spring and of same wire diameter as said medium hard spring and said soft spring.   
     
     
         2 . A spring unit according to  claim 1 , characterized in comprising at least a medium hard spring having number of convolution smaller than soft spring and bigger than hard spring and which can be in range from 6 to 11. 
     
     
         3 . A spring unit according to  claim 2 , characterized in comprising at least a medium hard spring made from steel material. 
     
     
         4 . A spring unit according to  claim 1 , characterized in comprising at least a soft spring having number of convolution bigger than medium hard spring and hard spring and that can be in range from 7 to 12. 
     
     
         5 . A spring unit according to  claim 4 , characterized in comprising at least a soft spring made from steel material. 
     
     
         6 . A spring unit according to  claim 1 , characterized in comprising at least a hard spring having number of convolution smaller than medium hard spring and soft spring and that can be in range from 5 to 10. 
     
     
         7 . A spring unit according to  claim 6 , characterized in comprising at least a hard spring made from steel material. 
     
     
         8 . A spring unit according to  claim 1 , characterized in comprising at least a soft spring located in proper order fitting different comfort levels along length of said carcass, at least a medium hard spring and at least a hard spring. 
     
     
         9 . A method for production of a spring system characterized in comprising the following steps:
 production of springs from steel wire to form a spring unit at spring machine and placement into nonwoven and bringing into spring strips;   while forming spring strips, production of hard springs in each line, in lower number of convolution with same wire diameter and increasing pretension in order to obtain hard comfort area in spring unit;   number of convolution is increased one step continuing medium hard springs and forming transition comfort area in the spring unit and thus production of next soft springs in higher number of convolution with same wire diameter and less pretension in order to obtain soft comfort area;   repeating mentioned different comfort areas along spring strip in a manner transition comfort area occurs between them;   feeding spring strips produced at spring machine to assembling machine in a manner high hard springs are in the beginning of strip;   obtaining different comfort areas by gluing pocket spring strips to each other from middle at assembling machine by adding hot melted glue and/or from bottom and top by adding nonwoven, and providing gradual transition between comfort areas.